PROBLEM TO BE SOLVED: To provide an underpants type absorbent article capable of inhibiting or reducing the occurrence of trimming in manufacture, and having excellent covering performance for the inguinal part and the hip.SOLUTION: An underpants type absorbent article 1 includes: an abdominal side sheet member 2A disposed on the abdominal side of a wearer a back side sheet member 2B disposed on the back side of the wearer and an absorbent body 3 stretched therebetween and fixed, and has a waist opening part WO and a pair of leg opening parts LO, LO. The abdominal side sheet member 2A and the back side sheet member 2B have elasticity in an article cross direction Y, and at least in one of them, third sheet members 4A, 4B having elasticity in an article vertical direction X are connected to a center line Ly side in the article cross direction. The third sheet members 4A, 4B are joined to the absorbent body 3 with the parts overlapping the absorbent body 3 elongated toward the center line LY side in the article cross direction, and have a part E gradually increased in length in the article vertical direction X as it goes close to the absorbent body 3 in the vicinity of the absorbent body 3.
